Abstract
This paper describes an automatic and robust approach to convert 3D CAD assembly models into unstructured hexahedral meshes that are conformal to the given B-Reps (boundary-representations) with sharp feature preservation. In previous works, we developed an octree-based isocontouring method to construct unstructured hexahedral meshes for manifold and non-manifold domains. However, sharp feature preservation still remains a challenge. In the current algorithm, boundary features such as sharp curves and NURBS (non-uniform rational B-Splines) surface patches are first extracted from the given B-Reps. An octree-based isocontouring algorithm is then carried out to create unstructured hexahedral meshes, detecting and preserving all the sharp features. After this stage, a two-step pillowing technique is adopted to eliminate triangle-shaped quadrilateral elements along the sharp curves and “doublets”. To further improve the mesh quality, a combination of smoothing and optimization is used. The developed algorithm is robust, and it works for single-component manifold domain, as well as multiple component non-manifold domains. We have applied our algorithm to several complicated CAD models and assemblies. Valid meshes are generated and quality statistics are given.
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Qian, J., Zhang, Y. (2010). Sharp Feature Preservation in Octree-Based Hexahedral Mesh Generation for CAD Assembly Models. In: Shontz, S. (eds) Proceedings of the 19th International Meshing Roundtable. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-15414-0_15
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DOI: https://doi.org/10.1007/978-3-642-15414-0_15
Publisher Name: Springer, Berlin, Heidelberg
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